Support KClass.nestedClasses

compiler/testData/codegen/boxWithStdlib/reflection/classes/nestedClasses.kt

@@ -0,0 +1,58 @@
+// FULL_JDK
+
+import kotlin.reflect.KClass
+import kotlin.reflect.jvm.*
+import kotlin.test.assertEquals
+
+class A {
+    companion object {}
+    inner class Inner
+    class Nested
+    private class PrivateNested
+}
+
+fun nestedNames(c: KClass<*>) = c.nestedClasses.map { it.simpleName ?: throw AssertionError("Unnamed class: ${it.java}") }.toSortedList()
+
+fun box(): String {
+    // Kotlin class without nested classes
+    assertEquals(emptyList<String>(), nestedNames(A.Inner::class))
+    // Kotlin class with nested classes
+    assertEquals(listOf("Companion", "Inner", "Nested", "PrivateNested"), nestedNames(A::class))
+
+    // Java class without nested classes
+    assertEquals(emptyList<String>(), nestedNames(Error::class))
+    // Java class with nested classes
+    assertEquals(listOf("State", "UncaughtExceptionHandler"), nestedNames(Thread::class))
+
+    // Built-ins
+    assertEquals(emptyList<String>(), nestedNames(Array<Any>::class))
+    assertEquals(emptyList<String>(), nestedNames(CharSequence::class))
+    assertEquals(listOf("Companion"), nestedNames(String::class))
+
+    assertEquals(emptyList<String>(), nestedNames(Collection::class))
+    assertEquals(emptyList<String>(), nestedNames(MutableCollection::class))
+    assertEquals(emptyList<String>(), nestedNames(List::class))
+    assertEquals(emptyList<String>(), nestedNames(MutableList::class))
+    assertEquals(listOf("Entry"), nestedNames(Map::class))
+    assertEquals(emptyList<String>(), nestedNames(Map.Entry::class))
+    assertEquals(emptyList<String>(), nestedNames(MutableMap.MutableEntry::class))
+
+    // TODO: should be MutableEntry. Currently we do not distinguish between Map and MutableMap.
+    assertEquals(listOf("Entry"), nestedNames(MutableMap::class))
+
+    // Primitives
+    for (primitive in listOf(Byte::class, Double::class, Float::class, Int::class, Long::class, Short::class, Char::class)) {
+        assertEquals(listOf("Companion"), nestedNames(primitive))
+    }
+    assertEquals(emptyList<String>(), nestedNames(Boolean::class))
+
+    // Primitive arrays
+    for (primitiveArray in listOf(
+            ByteArray::class, DoubleArray::class, FloatArray::class, IntArray::class,
+            LongArray::class, ShortArray::class, CharArray::class, BooleanArray::class
+    )) {
+        assertEquals(emptyList<String>(), nestedNames(primitiveArray))
+    }
+
+    return "OK"
+}